The company said in a statement that the deal has received all necessary regulatory approvals, and they expect it to close Oct. 1.

The acquisition is a step toward their ultimate goal of separating back into two new public companies — one focused on replacement auto parts and the other on powertrain technology. Now, both companies compete in both sectors.

The companies said in April that split is expected to happen in the first half of next year.

Lake Forest, Ill.-based Tenneco plans to pay for the acquisition with $800 million in cash, about 30 million Tenneco shares and the assumption of debt.

Tenneco said the three proposals passed with more than 90 percent of shares voted in favor.

After the combined companies split up again, it's expected that headquarters for each company will remain in the Detroit and Chicago areas.

The deal marks a payoff for Icahn, who bought up Federal-Mogul debt before the company's 2001 bankruptcy. That debt converted to ownership as part of the company's exit from bankruptcy years later. He increased his stake over time, eventually taking full ownership of the company in 2017 in a roughly $300 million deal after nearly a year of posturing with F-M's shareholders.

Tenneco posted $9.27 billion in total revenue in fiscal 2017 and reported net income of $274 million. Together, General Motors and Ford Motor Co. comprised more than a quarter of the company's sales last year.

Federal-Mogul posted $7.43 billion in total sales in 2016 and $82 million in net income, the latest year available. In 2015 it had a $110 million loss, and a $168 million loss in 2014. None of Federal-Mogul's customers in 2016 accounted for more than 10 percent of its overall revenue, the company said in its annual report.